I’m waiting for the Tarmac Sl8 release myself as I have a gravel bike and want a road race specific bike, if I only had one drop bar bike though would probably look at the gen 4 Domane SL6, would have a set of 30c GP 5000s and a set of 38c Pathfinder Pros on another wheelset.
The Domane/Roubiax is a different bike. Those are like a Porsche 911, which is a bit more flexible than most 2-seat sports cars but not as ‘pure’ of a sports car. The better ride and back seat area make the 911 everyday usable and flexible…but still does all the sports car things.
-The Domane/Roubiax can take gravel tires, which open up a lot of options for soft-roading and exploring/traveling.
-Domane/Roubiax are a bit less aero (Tarmac SL7 / Emonda SL; not Tarmac SL6), if you’re regularly riding with a group of testosterone on the road, but the real world difference is only in those brief moments when you’re in the wind at top speed. The other difference is seating position with the Emonda/Tarmac for the rider who wants the bars as low as possible for aero. A lot of the real world bike aero is negated by water bottles, saddle bags, and your body on the bike.
-If you’ve just got one bike and you do more than angry road group road rides, I’d go Domane. The Tarmax SL7 would probably make me feel the coolest though. The 2024(?) Emonda ALR would be the best use of your money.
The downtube trunk on the Domane and Roubaix is a great feature , as your bike will look cooler without a saddlebag.
The Specialized Aethos is probably in between those two groups)
Buy the best paint job.
Trek “5” vs “6” - for Shimano mechanical builds (not Sram, not AXS wireless/ Di2), you’re looking at 105 vs Ultegra. Both are top notch ,and it’d just be the .5lb weight. The “6” also has nicer wheels, but not worth considering. Most of these are 11sp builds- 12sp really doesn’t bring anything to the party here. 2x12sp is silly. The SL6 Pro has ok-nice wheels, and I’d personally do that over 105 Di2 12sp.
Otherwise, SRAM vs Shimano and electonic vs traditional. On the SRAM builds, again, it’d be Rival vs Force, so just weight again. Wireless vs Mechanical - I have both, electronic doesn’t really add anything. Buy the best paint job
If you’re going to travel, with a bike in a case, understand what it’d take to pack up the bike. The Emonda has a seat mast, which might not be an issue if you’re looking at a bike smaller than a 58. They all have the same cable routing system (FSA ACR).
On “trek 5 vs 6” or Specialized “comp/sport/expert”, I’d spend the price difference on stuff like shoes, pedals, power meter, tires (toss the stock tires anyway), etc. And the better paint job.
I’d skip the Orro. Have you looked at something like the Canyon Ultimate? Rose, Orbea, Cube?
The current 2023 SL6 is a notch below. It is the lowest spec SL6 held over from before the SL7 was introduced. I’m not saying it’s a bad bike at all. They just dumbed it down a tiny bit - lowest spec carbon, round seatpost, external seatpost clamp. They got rid of the aero seatpost. (Some may find that desirable!)
If you spec a Tarmac SL7 with the same parts as an Emonda SL6, the Tarmac will cost about $1000 more. Specialized really pushed the price increases during the pandemic IMO.